1. Field of the Invention
The present invention rnlates to an electrical connector, and particularly to a high density electrical connector having a plurality of circuit boards for high speed signal transmission.
2. Description of Related Art
With the development of communication and computer technology, high-density electrical connectors with conductive elements in a matrix arrangement are desired to construct a large number of signal transmitting paths between two electronic devices. The high-density electrical connectors are widely used in internal connecting systems of severs, routers and the other like devices requiring high-speed data processing and communication. Such high-density electrical connectors are disclosed in U.S. Pat. Nos. 6,152,747, 6,267,604, 6,171,115, 5,980,321, and 6,299,484. These high-density connectors each generally comprise two mating connector halves, i.e., a plug connector half connecting with a main board and a receptacle connector half connecting with a daughter card and for mating with the plug connector half, thereby establishing an electrical circuitry between the daughter card and the main board. The plug or receptacle connector half of such a high-density connector is called a xe2x80x9cback plane connectorxe2x80x9d in the art, and such term is used hereafter through the disclosures.
Commonly, a backplane connector comprises a plurality of wafers side-by-side arranged; each wafer has a dielectric housing, a plurality of signal terminals and a plurality of grounding terminals staggeredly disposed in the housing. Since the signal and grounding terminals are independently assembled to the housing, the assembling of the connector is laborious and the manufacturing cost thereof is accordingly high. Furthermore, the grounding terminals in one wafer of the connector only engage with grounding traces of a single corresponding printed substrate in the connector; such a design cannot obtain an optimal performance for signal transmission through the connector.
Hence, an improved backplane connector is required to overcome the disadvantages of the prior art devices.
Accordingly, a first object of the present invention is to provide a backplane connector having an improved grounding bus which can establish a reliable electrical connection with two adjacent printed substrates in the backplane connector.
A second object of the present invention is to provide a backplane connector having a simplified and integrated grounding structure so that the connector can be easily assembled.
To fulfill the above objects, an electrical connector, to be mounted on a mother board, in accordance with the present invention comprises an insulative housing defining a plurality of channels, a plurality of printed substrates partially received in the channels, and a spacer assembled with the printed substrates. The spacer includes a plurality of wafers defining a plurality of tunnels between every two adjacent wafers for partially receiving corresponding printed substrates. Each wafer has a body portion, a plurality of terminals molded with the body portion and conductively contacting with corresponding signal traces formed on the printed substrate, and a grounding bus covering on the body portion. Each grounding bus forms a plurality of grounding tabs for conductively contacting with grounding traces formed on the printed substrate. Each grounding bus forms a plurality of grounding members locating on opposite sides of the body portion for conductively contacting with grounding traces formed on two corresponding printed substrates inserted into two adjacent tunnels associated with the grounding members.